Laboratory analysis instrument

ABSTRACT

A kit of implements for laboratory analysis, comprising a tube to contain a sample to be ground, a rod to be appropriately insertible into the tube, and a cap to tightly close the open mouth of the tube, among which the tube is so designed as to be commonly usable either in a grinding operation in combination with the rod or in a sequential physical and/or chemical treatment such as blending, centrifugation, extraction, etc., in combination with the cap, respectively, so that the sequential dual steps may be performed in immediate succession, while eliminating the necessity of transferring the ground sample from a grinding tube to a centrifugal precipitation tube as required in the conventional manner, thereby to prevent loss of the ground sample, which inevitably occurs due to the transfer procedure, thereby to effectively preserve high reliability of the experiment results, and furthermore to substantially save time and trouble required in such transfer procedure during the experiment operation.

[ LABORATORY ANALYSIS INSTRUMENT [76] inventors: Yoshiko Saiki; Atsushi Saiki, both of 30-3, S-chome Chuo, Ota-ku, Tokyo, Japan [22] Filed: Nov. 17, 1972 [21] App]. No.: 307,534

[52] US. Cl 23/259, 23/292, 195/127, 241/199.1 1 [51] Int. Cl...... B011 11/00, B02c 19/08, C12k 1/10 [58] Field of Search 23/259, 253 R, 292; 241/199.l1; 195/127, 104; 233/26 [5 6] References Cited UNITED STATES PATENTS 3,773,468 ll/l973 Hubbard et al 23/259 OTHER PUBLICATIONS VWR'Scientific Catalogue 72, Received at US. Patent Office 10/12/71. Pages 1218, 1219.

Sargent-Welch Catalogue No. l 19, Scientific Laboratory instruments, Apparatus & Supplies p. 778 (5-62330) & page 231 (centrifuge tubes) 1971.

[4 1 Feb. 11, 1975 Primary ExaminerJoseph Scovronek Assistant E.raminerMichael S. Marcus Attorney, Agent, or Firm-Waters, Roditi, Schwartz & Nissen [5 7] ABSTRACT A kit of implements for laboratory analysis, comprising a tube to contain a sample to be ground, a rod to be appropriately insertible into the tube, and a cap to tightly close the open mouth of the tube, among which the tube is so designed as to be commonly usable either in a grinding operation in combination with the rod or in a sequential physical and/or chemical treatment such as blending, centrifugation, extraction, etc., in combination with the cap, respectively, so that the sequential dual steps may be performed in immediate succession, while eliminating the necessity of transferring the ground sample from a grinding tube to a centrifugal precipitation tube as required in the conventional manner, thereby to prevent loss of the ground sample, which inevitably occurs due to the transfer procedure, thereby to effectively preserve high reliability of the experiment results, and furthermore to substantially save time and trouble required in such transfer procedure during the experiment operation.

4 Claims, 4 Drawing Figures PATENTEI] FEB] 1 I875 FIG. l.(b) PRIOR ART FIG FIG.2.(0)

1 LABORATORY ANALYSIS INSTRUMENT BACKGROUND OF THE INVENTION This invention relates to a kit of implements for a certain analysis operation in the laboratory, and particularly to a new and improved implement kit which can be commonly adapted for sequential laboratory operations such as grinding, blending, centrifugation, extraction, etc.. More particularly, the present invention relates to a kit of implements which is adapted to grind a sample in a very effective manner and is specifically designed to integrally cover the abovementioned laboratory operations by making the implement kit versatilely serviceable.

In such sequential laboratory steps, use is ordinarily made of a kit of implements which comprises a tube and a rod for grinding a sample into small pieces and another tube for further sequential analysis operations in the laboratory.

When conducting grinding and further sequential procedures in the laboratory by using the conventional means for analysis of the ground sample, there is required an unavoidable step, i.e., to transfer the sample, after being ground, from a grinding tube such as a Potter-Elvehjem homogenizer or a mortar to a centrifugal precipitation tube or the like. During such transfer pro cedure, however, it is inevitable that there occurs a contingent loss of the ground sample which is liable to stick to both the grinding tube and the rod during a grinding procedure, and that loss of the sample unavoidably causes the analysis result to be intolerably unreliable in view of the required accuracy, such as that in a gravimetric measurement of the sample, to follow in a series of analysis operations.

On the other hand, such transfer procedure and further procedure in an attempt to maintain the amount of the sample loss to a minimum undoubtedly subjects the laboratory staff to nervous strain and causes loss of operational time.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an instrument which is usable for dual sequential steps in the laboratory analysis procedures, i.e., a grinding procedure and a further sucessive procedure such as blending, centrifugation, extraction, etc. More specifically, an object of this invention is to provide an instrument which is commonly adaptable to the above mentioned two steps, thereby to eliminate the necessity of transferring a ground sample from one instrument to another.

Another object of the invention is to provide an instrument which affords, by eliminating the necessity of the transfer procedure, a much higher reliability in the analysis results owing to the prevention of the loss of the sample which is liable to remain within the instrument during the transfer procedure.

Still another object of the invention is to provide the above stated instrument in the form of a kit of implements comprising a tube and a rod for grinding performance, which are individually provided with dual, fine and rough grinding surfaces around the circumferential surfaces thereof and in the bottom areas thereof, respectively, for performing effectively a grinding operation.

A further object of the invention is to provide an instrument which can be economically made by making the instrument integral or of one-piece structure with dual serviceability instead of the conventional twopiece kit of the implements for a single purpose.

A still further object of the invention is to provide an instrument which substantially relieves the laboratory staff of nervous strain due to transfer procedures and also substantially prevents time loss in experimental operations.

An additional object of the invention is to provide a kit of implements which may be stored under refrigeration, after being tightly capped, leaving the sample within the tube of the kit free from the trouble of transferring the sample.

According to the present invention, briefly summarized, there is provided an instrument which is commonly serviceable for grinding and further successive procedures, consisting essentially of a tube and a rod as a composite kit for a grinding operation, and a tube and a cap as another kit for a further successive procedure such as blending, centrifugation, extraction, etc., by which respective combination of the implements the two steps of grinding and a sequential procedure can readily be performed in immediate succession, making possible such laboratory analysis operations substantially free from loss of the sample during the transfer procedure from one implement to another, and therefore, resulting in high accuracy of the experimental results. Furthermore, the laboratory staff can be substan tially relieved from nervous strain and time loss in a transfer procedure, whereby reliable experimental results can be achieved.

BRIEF DESCRIPTION OF THE DRAWING The nature, principle and details of the invention will be more clearly apparent from the following detailed description with respect to preferred embodiment of the invention, when read in conjunction with the accompanying drawing, in which like parts are designated by like reference numerals;

In the drawing:

FIGS. 1(a) and 1(b) are perspective view showing, in combination, a set of the conventional Potter-Elvehjem instrument and the centrifugal precipitation tube for a centrifugal analysis operation; and

FIGS. 2(a) and 2(b) are sectional view, partly in schematic form, showing, in combination, one example of the laboratory analysis instrument embodying the invention.

DETAILED DESCRIPTION Referring to FIG. 1(a), when conducting a grinding operation by conventional means such as a Potter- Elvehjem homogenizer, it is required to first put a sample to be ground into a Potter-Elvehjem homogenizer l (hereinafter referred to as a Potter tube) having a rough grinding surface 2 in the interior thereof, then to insert thereinto a rod 4 having a grinding part 3 at the bottom end thereof which appropriately fits the interior surface of the Potter tube 1 (hereinafter referred to as a grinding rod), and then to grind the sample into small pieces by applying appropriate sliding motions.

After the sample has been reduced by grinding into the required pieces, a solvent is placed into the Potter tube I to dissolve the ground sample, or at least to keep the sample in wet condition particularly when there is the possibility of the ground sample being scattered into the air during a blending or shaking procedure. Re-

ferring now to FIG. 1(b), the dissolved or wetted sample is then transferred to a centrifugal precipitation tube 5 (hereinafter referred to as a centrifuge tube) or the like for a sequential analysis operation. For such a grinding operation, a mortar or sea sand is occasionally applied.

When transferring the sample from the Potter tube 1 to the centrifuge tube 5 for instance, however, a substantial amount of the sample inevitably remains in the Potter tube even when caution is exercised. Moreover, when sea sand is used, the sample is left unhomogenized, thereby resulting in a poor yield of extraction. Particularly when analyzing the sample to be weighed in terms of a gamma (y) unit (N.B., ly=0.00l mg), there is considerable error in the result of the gravimetric analysis, thus inevitably resulting in considerably poor reliability in the experiment results. Furthermore, such a transfer procedure from one experiment implement to another tends to interrupt the smooth succession of the operational procedures of the experiment, giving rise to undesirable and wasteful nervous strain on the part of the laboratory staff, and further loss in the operational time.

The present invention, in consideration of the above mentioned defects of the conventional means for laboratory analysis, contemplates advantageous means which completely eliminates the necessity of a transfer procedure of the sample after it is ground and affords an immediately successive operation of the sequential analysis.

One example of an instrument which integrally covcrs grinding and further successive procedures according to the invention will now be described, in conjunction with the accompanying drawing.

Referring now to FIG. 2(a), the interior of a glass tube (hereinafter referred to as a Potter tube) is provided with a fine grinding surface 11 almost up to the open mouth thereof, and a fine frosted surface at the inner surface of the open mouth. Surface 11, furthermore, is shifted to a coarse grinding surface toward the bottom area 12, thus providing a coarse surface 13. As shown in FIG. 2(b), a stopper 16 has a frosted circumferential surface, and is provided for tightly fitting into and closing the mouth of the Potter tube so as to prevent the dissolved sample from leaking when shaken violently in a centrifuge. The enlarged diametral portion 17 of a rod designed for grinding the sample is provided with a coarse surface in the bottom area 18 thereof and with a fine grinding surface on the outer circumferential surface 19 thereof.

The grinding instrument embodying the above mentioned features of construction may be used in the following analytical operations.

In FIG. 2(a), the sample to be ground is, after being priorly weighed, put into the Potter tube 10 and then ground by means of the rod 15. As there is provided the coarse grinding surface in the bottom area 18 of the enlarged diametral portion 17 of the grinding rod 15, area 18 contacts with the coarse grinding surface 13 at the bottom area 12 of the Potter tube 10, so that an effective grinding is obtained on the above mentioned sample. After this grinding operation has been completed, a solvent is poured into the Potter tube 10 in order to dissolve the sample. It is recommended that this solvent be poured thereinto in such a manner that the solvent will wash the ground sample away from the rod 15 within the Potter tube 10 so as to prevent loss of the sample which might stick to the rod, in order to precisely preserve the amount of the sample.

In the following procedure, now referring to FIG. 2(b), the Potter tube 10, after being closed with a stopper 16 is then placed onto an appropriate centrifuge for a centrifugal precipitating operation or for other procedures such as blending, shaking, and extraction. After this operation, a gravimetric measurement is conducted on either a precipitate or a supernatant liquid for an analytical experiment to follow.

When there appear two or more layers of the dissolved sample in the tube, it is ordinarily necessary to repeatingly add necessary solvent until the layers are removed by using such implements as a pipette or a needle.'ln this particular case, it is obviously advantageous to apply such a multi-purpose tube according to this invention, since such repeated procedures are operable with the same tube, leaving the sample therewithin.

According to the present invention, as described above, by virtue of a coarse grinding surface provided in the interior of the Potter tube, the grinding and further successive procedures can be readily performed without any interruption, thus not only preventing errors from occurring during the transfer procedure of the ground and dissolved sample from a Potter tube to a conventional centrifuge tube or the like, but also effectively shortening the time required for such an analysis operation, and further providing such an economic advantage as enabling the analysis instrument to be made as integral implement instead of the conventional two-piece kit of the implements for independent purposes. Above all, the provision of the both fine and coarse grinding surfaces for the grinding rod and Potter tube, respectively, results in a remarkably effective grinding operation when compared with the conventional means.

The glass tube as referred to in the foregoing disclosure may be made of any other material as, for example a plastic resin, metal or the like having a characteristic which suits its use to accomplish the desired purpose.

Such a kit of implements may also be applied to general use such use in the home or commercial kitchen or at the table as a container of foodstuff for blending, shaking, etc. and for refrigeration, the foodstuff being left therewithin.

We claim:

1. A laboratory analysis instrument comprising, in combination, a tube having a closed bottom and a coarse grinding surface on the inner bottom area thereof, a fine grinding surface at the inner circumferential wall surface extending substantially to the open mouth of said tube, and a finely frosted surface on the inner circumferential wall surface in the upper mouth area of said tube; a grinding rod provided at its lower end with an enlarged diametral portion snugly insertible into said tube for grinding a sample placed into said tube, said enlarged portion having a coarse grinding surface at the bottom area of said portion and having a fine grinding surface at the circumferential wall surface of said portion; and a stopper having a frosted circumferential surface for tightly fitting into and closing the mouth of said tube to prevent thereby leakage of a sample dissolved by a solvent in said tube when shaken in a centrifuge after grinding of said sample.

interior bottom surface of said tube.

4. The laboratory analysis instrument as defined in claim 3 including a peripheral lip portion about the top rim of said tube. 

1. A LABORATORY ANALYSIS INSTRUMENT COMPRISING, IN COMBINATION, A TUBE HAVING A CLOSED BOTTOM AND A COARSE GRINDING SURFACE ON THE INNER BOTTOM AREA THEREOF, A FINE GRINDING SURFACE AT THE INNER CIRCUMFERENTIAL WALL SURFACE EXTENDING SUBTANTIALLY TO THE OPEN MOUTH OF SAID TUBE, AND A FINELY FROSTED SURFACE ON THE INNER CIRCUMFERENTIAL WALL SURFACE IN THE UPPER MOUTH AREA OF SAID TUBE; A GRINDING ROD PROVIDED AT ITS LOWER END WITH AN ENLARGED DIAMETRAL PORTION SNUGLY INSERTIBLE INTO SAID TUBE FOR GRINDING A SAMPLE PLACED INTO SAID TUBE, SAID ENLARGED PORTION HAVING A COARSE GRINDING SURFACE AT THE BOTTOM AREA OF SAID PORTION AND HAVING A FINE GRINDING SURFACE AT THE CIRCUMFERENTIAL WALL SURFACE OF SAID PORTION; AND A STOPPER HAVING A FROSTED CIRCUMFERENTIAL SURFACE FOR TIGHTLY FITTING INTO AND CLOSING THE MOUTH OF SAID TUBE TO PREVENT THEREBY LEAKAGE OF A SAMPLE DISSOLVED BY A SOLVENT IN SAID TUBE WHEN SHAKEN IN A CENTRIFUGE AFTER GRINDING OF SAID SAMPLE.
 2. A laboratory analysis instrument as defined in claim 1 wherein the interior bottom surface of said tube has a substantially spherical contour.
 3. The laboratory analysis instrument as defined in claim 2 wherein the bottom surface of said grinding rod has a curved surface conforming substantially to said interior bottom surface of said tube.
 4. The laboratory analysis instrument as defined in claim 3 including a peripheral lip portion about the top rim of said tube. 